With it now confirmed that nine Ulster players will represent four different countries at the Rugby World Cup, the Ulster management will view Friday's clash very much in the context of the start of the RaboDirect Pro12 next week when Ulster entertain Glasgow Warriors.
With captain Johann Muller and vice-captain Rory Best both New Zealand bound, Chris Henry will take charge of the Ulster side during the World Cup period and will lead the team against 'Quins.
As expected, head coach McLaughlin has used the pre-season friendlies to rotate his squad.
Only props Paddy McAllister and Jerrry Cronin and the second row partnership of Lewis Stevenson and Neil McComb are retained this week from the youthful Ulster side that defeated Neath 34-15.
Ian Humphreys and Nevin Spence will get their first taste of action on Friday night, having both recovered from shoulder surgery.
Dan Tuohy, who has been named amongst the replacements, is fit again after recovering from the severe hamstring tear he sustained against the Dragons last May.
Gates open at Ravenhill at 6pm and kick-off is 7.30pm. Tickets for the match, starting at £12 for adults, are still available from the Ravenhill Ticket Office, www.ulsterrugby.com, SS Moores and other usual outlets, and are part of the 2011/12 Season Ticket package.
Ulster Rugby would like to remind supporters that this season ticket zoning and scanning will be in operation at the ground.
Fans should check their tickets to ensure that are entering through the correct gate. Further details are available here.
ULSTER (v Harlequins): Adam D'Arcy; Conor Gaston, Darren Cave, Nevin Spence, Conor Gilroy; Ian Humphreys, Paul Marshall; Paddy McAllister, Andi Kyriacou, Jerry Cronin, Lewis Stevenson, Neil McComb, Pedrie Wannenburg, Willie Faloon, Chris Henry (capt).
Replacements: Nigel Brady, Callum Black, Adam Macklin, Tim Barker, Dan Tuohy, Robbie Diack, Ian Porter, Paddy Jackson, Ian Whitten, Luke Marshall, Peter Nelson.